Circumference and Area Calculator

Circle calculator
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The area formula of a circle is pi*radius squared, which can be expressed in letters as: S=πr² or S=π*(d/2)². (π represents pi, r represents radius, and d represents diameter).

The circumference of a circle is: C = π * d or C=2*π*r (where d is the diameter of the circle and r is the radius of the circle).